#!/bin/bash

:<<EOF
Given a text file file.txt, print just the 10th line of the file.

Example:

Assume that file.txt has the following content:

Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Line 10
Your script should output the tenth line, which is:

Line 10
Note:
1. If the file contains less than 10 lines, what should you output?
2. There's at least three different solutions. Try to explore all possibilities.
EOF

line=`cat file.txt | wc -l`
if [ $line -lt 10 ]; then
    echo "The number of row is less than 10"
else
    awk '{if(NR==10){print $0}}' file.txt
fi